scangauge instrumentation

[coehorn]

Installed a ScanGauge II in on '03 Tacoma 4x4.

As a test of accuracy for the horsepower x-gauge, I did an (old-mans version) of a fast takoff. From a stop, I did a smooth roll-on of the throttle to about 80 or 90% of available throttle, shifting at ~3500 RPM. Scanguage reported a reading of 135 horses which sounds pretty good cause the 2.7 I4 is rated at 150 horses.

Around town, on mostly flat land with small hills, it appears that my peak HP use is around 60 HP. Most of use is around 30 to 40 horses. I haven't scoped out highway travel yet.

If I were to replace the 2.7 I4 with a micro-diesel or electric motor, should I be looking at torque over horsepower ratings? Seems I recall an expression - something like - we don't drive horsepower, we drive the torque. Any other readings I should be looking at on the Scangauge?

[Arragonis]

There are probably better replies but HP is a mathematical thing, a measure of work done whereas torque is a measure of 'twist'. The formula is something like

(torque (lb/ft) * rpm) / 5252

I'm not sure about the hp readings from the SG2 as I've had mine 48 hours now

If you want to swap then you need also to match the rev range of the engine to your gearing and weight - maybe an axle swap or something. My TDI has 30 mph/1000 in top but the car is very light (for a modern car that is, its still too heavy IMHO).

I'm not sure how electric motors work in terms of rpm, torque and efficiency except they make max torque from stop. But I'm keen to learn more so I will watch other replies.